Marine vessel with propeller

Abstract

A marine vessel having a propeller tunnel possessing a flow-favorable cross-sectional configuration following the flow lines of the water. Within the propeller tunnel there is mounted a propeller essentially throughout one-half of its circumference. An adjustable control plate can be extended in order to detach the flow of the water from the surface of the tunnel during rapid travel of the marine vessel. In this case, the propeller functions as a partially immersed propeller at a high rotational speed. There can be provided a control device which adjusts the control plate as a function of the rotational speed range within which the propeller operates. The propeller can be an adjustable propeller conjointly adjustable with the control plate.

What we claim is: 
     
       1. A marine vessel comprising: a hull having a floor portion;   a tunnel provided at the floor portion of said hull;   at least one propeller which is located essentially throughout approximately one-half of its circumference within said tunnel;   said tunnel extending in the lengthwise direction of said hull;   said tunnel possessing a flow-favorable cross-sectional configuration which follows flow lines of the water;   an adjustable control plate located forwardly of said propeller at a transition region between a surface of the floor portion and said tunnel;   means for adjusting said control plate between a first position and a second position;   said control plate when in said first position merging with the surface of said tunnel and permitting a streamlined shaped flow of the water through said tunnel so that said propeller is substantially fully immersed in the flow of water; and   said control plate, when in said second position, being extended and spaced from the surface of the tunnel and causing detachment of the water flow from the surface of the tunnel so that said propeller is only semi-immersed in the flow of water.   
     
     
       2. The marine vessel as defined in claim 1, wherein: said hull has a stern   said tunnel, viewed from the stern of the hull, possesses an essentially semi-circular shaped configuration and encloses the circumference of the propeller.   
     
     
       3. The marine vessel as defined in claim 1, wherein: said tunnel is bounded at least partially by a surface;   said surface having a cross-sectional shape which, in the lengthwise direction of the hull, follows the flow lines of the water; and   said surface being formed by straight lines extending essentially perpendicular to the lengthwise direction of the hull.   
     
     
       4. The marine vessel as defined in claim 1, wherein: said means for adjusting said control plate comprises a control device for actuating the control plate as a function of a rotational speed range of the propeller.   
     
     
       5. The marine vessel as defined in claim 1, wherein: said propeller comprises an adjustable propeller having vanes whose pitch angle are adjustable during operation of the propeller; and   control means for adjusting the vanes of the propeller as a function of the rotational speed range of the propeller.   
     
     
       6. The marine vessel as defined in claim 1, wherein: said tunnel is open at a rear end thereof during operation of the marine vessel and said rear end remains unaffected in its cross-sectional area by said control plate.   
     
     
       7. The marine vessel as defined in claim 1, wherein: the cross-sectional configuration of said tunnel, viewed in the lengthwise direction of the hull, possesses a portion which merges with a surface of the floor portion of the hull;   said merging portion being bounded by a convex line after which follows a further portion bounded by a concave line.